Add the requested inputs
Use the labelled fields in the workspace above. If example values are provided, try them first or replace them with your own.
Digital & media · Free online tool
Image aspect ratio calculator
Reduce a width and height to a ratio or calculate a matching missing dimension.
3 guest runs per rolling 24 hours10 with a free accountPrivate inputsMobile-friendly
Image aspect ratio calculator workspace
Runs locally in your browser
Result
Reduced ratio—
Matching dimensions—
Decimal ratio—
Width from target height—
Height from target width—
Use it with confidence
How to use the image aspect ratio calculator.
Calculate and review
Use the main action when needed. The ratio is reduced by the greatest common divisor. Resizing uses new height = old height × new width ÷ old width.
Try a worked example
1920 × 1080 reduces to 16:9; at 1280 pixels wide the matching height is 720.
Check the assumptions
Cropping to a different ratio removes content; resizing to the same ratio preserves the frame.
Helpful answers
Image aspect ratio calculator FAQs.
Is the image aspect ratio calculator free?
Yes. Guests receive 3 runs per rolling 24 hours, verified free accounts receive 10, and Premium subscribers receive unlimited normal use.
Does UtilHub upload or save my inputs?
No. This tool runs in your browser and UtilHub does not receive or store the values you enter. Your browser or device may still retain normal local history or form data.
How does this image aspect ratio calculator work?
The ratio is reduced by the greatest common divisor. Resizing uses new height = old height × new width ÷ old width.
What should I check before using the result?
Cropping to a different ratio removes content; resizing to the same ratio preserves the frame.